Document the watchdog disable option which can be used if the hardware
automatic suspend option is broken.

Based on commit c514430c ("dt-bindings: watchdog: da9062: add
suspend disable option").
Signed-off-by: Primoz Fiser <primoz.fiser@norik.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Adam Thomson <DLG-Adam.Thomson.Opensource@dm.renesas.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220422072713.3172345-1-primoz.fiser@norik.comSigned-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>